1. Field of the Invention
The present invention relates to a method for thinning the substrate of an EL (electroluminescence) device.
2. Description of the Related Art
Conventionally, attempts have been being made widely to put into practical use EL devices such as inorganic EL devices and organic EL devices as displays and illumination devices of thin, lightweight portable apparatus because they exhibit high luminance and emit light by themselves. Those EL devices have a structure that an EL element portion having a pair of electrode layers at least one of which is a transparent electrode layer and a light-emitting layer interposed between the two electrode layers are formed on a substrate.
In those EL devices, to reduce the thickness and weight of the entire device, it is desired to employ a thin substrate.
However, when attempted to form an EL element portion on a thin glass substrate, for example, it may become difficult to manufacture an EL device because the operability is low in each manufacturing step due to bending of the substrate and other problems. It is therefore necessary to use a thick glass substrate in manufacture.
Liquid crystal display devices are the same as EL devices in that a display element portion is formed on a glass substrate(s). However, in liquid crystal display devices, since the display element portion is disposed between two glass substrates, a method of thinning both glass substrates by immersing the liquid crystal display device in an etching liquid has been proposed as disclosed in JP-A-8-262419, for example.